For mounting sensors, such as video cameras, photographic equipment, infrared sensors, etc., for example, on vehicles such as airplanes, helicopters, land vehicles or aquatic vessels, etc., gimbal mounts are often used. To do so, the sensor is mounted on the gimbal mount which is in turn fastened to a part of the vehicle. Gimbal mounts allow movement of the sensor about a number of axes, usually a roll axis, a yaw axis and a pitch axis. There may also be multiple roll, yaw and/or pitch axes. The existing axes are therefore structurally nested one inside the other to enable movement of the sensor about all existing axes. For active movement about the axes provided, individual axes or all axes may also be driven. This makes it possible to position and/or align the sensor that is mounted on the gimbal mount by means of active control of the axes in any desired manner (within the limits of movement). This is important in particular when the sensor must remain aligned at a certain point during the movement of the vehicle. The inner axes are often used for fine positioning and the outer axes are used for approximate positioning of the sensor. Such a gimbal mount is described in U.S. Pat. No. 7,561,784 B2, for example.
However, while the vehicle is moving, vibrations are also introduced into the gimbal mount. A sensor on a gimbal mount must be decoupled from these vibrations for proper functioning and/or the position of the sensor (and/or its alignment) with respect to the vibrations must be stabilized. In the case of a sensor supported on a gimbal mount and mounted on a helicopter, vibrations of only a few angle seconds would result in a significant deviation from the targeted position. For example, without such vibration stabilization, no stable images could be recorded with a video camera because of such vibrations. Therefore, a great deal of effort has been put into the development of systems for vibration stabilization of gimbal mounts.
To keep vibrations away from the sensor, gimbal mounts have already been proposed, in which an inner gimbal mount is supported in a vibration-decoupled support in an outer gimbal mount, as disclosed in U.S. Pat. No. 5,897,223 A, for example. In this case, an inner gimbal mount is disposed in a spring-mounted shell, wherein the spring-mounted shell is itself supported in the outer gimbal mount. The inner gimbal mount is fastened to a gimbal mount point in the shell. Due to the spring-mounted shell the inner gimbal mount is vibration decoupled from the outer gimbal mount. However, this means that the inner gimbal mount needs to be mounted on its mount in a statically accurately balanced way. Any change in or replacement of the sensor is thus no longer readily possible because it would then be necessary to first repeat the static balancing of the mount of the inner gimbal mount.
U.S. Pat. No. 7,812,507 B2 describes a gimbal-mounted camera in which the gimbal mount is driven by a piezoelectric motor. A piezoelectric motor is known to be a motor in which vibration of one or more piezoelectric elements is converted into a movement of a movable part, for example, a linear movement. In a piezoelectric motor a vibration of the piezoelectric element is thus converted into a continuous movement (either a linear movement or a rotational movement). In the case of U.S. Pat. No. 7,812,507 B2, the vibration of a three-dimensional piezoelectric unit is utilized to move a spherical gimbal-mounted camera mount by means of friction. This movement is also utilized to compensate for vibrations. Thus, here, there is direct stabilization of the camera mount with respect to outer vibrations. However, because of the limited torque that can be generated with such a piezoelectric motor, there can only be low payloads and they can only be moved with poor dynamics. Rapid equalizing movements such as those which would be necessary for stabilizing vibrations of a higher frequency, cannot be implemented in this way, in particular not for payloads of a greater weight.